IF JIMMY CARTER is really serious about human rights and a reduction in arms sales, he'll have to back up his rhetoric with substantive policy decisions reflective of those concerns.

So far, Carter has had the look of a hypocrite on these issues. Not only has the United States sold over $4 billion in arms since Carter's May speech condemning excessive sales, but a large percentage of those deals have been completed with nations that systematically violate human rights.

Iran is a prime example. After berating Gerald Ford during the campaign for feeding the Shah's ravenous appetitie for arms, Carter has buckled under and approved the sale to Iran of seven sophisticated air radar systems worth $1.2 billion. Iran has now passed Israel as the largest recipient of American arms, and there is talk of striking more deals--these involving advanced bombers.

Such sales are immoral in view of the Shah's flagrant violation of human rights. The police state he runs has a reprehensible history of torturing political prisoners, and transactions with the Shah look decidedly hypocritical when squared against Carter's much-touted human rights stand.

In a larger sense, the deals raise serious questions about the Administration's overall judgement in its conduct of foreign affairs. Weapons sales to Iran could spark a new arms race in the Persian Gulf, and the personnel needed to train the Iranians will add to an American presence in that part of the world that is already too large. Of even greater importance is the absence of any notion of the Shah's plans, of what he wants to do with the billions the U.S. has been sending him.

It would be better if we didn't have to wait to find out. World peace and the integrity of the Carter Administration's foreign policy may depend on a more responsible policy on arms sales.